No Fear

A woman cannot feel fear because of a missing structure in her brain.

This woman is incapable of feeling afraid, but says she does feel other emotions. The reason for this strange condition is that the woman is missing a portion of her brain called the amygdala, which has been shown to help with emotional learning. The woman says that she has been threatened with a knife and held at gunpoint but did not feel the least bit afraid in either situation. Researchers tested her by having her handle dangerous snakes and a tarantula at a pet store and attend scary movies - she was never frightened!

The drawback to this "ability" is that she is also unable to process danger around her and subsequently avoid it - in reality, she is quite lucky to be alive! Researchers hope that by studying this woman they may find a way to treat patients with posttraumatic stress disorder.
(source)

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